1) Induced spawning techniques involve hormonal or environmental methods to stimulate fish to spawn outside of their natural season for intensive aquaculture.
2) Hormonal methods use pituitary extracts, HCG, or LHRH to stimulate the hypothalamus-pituitary-gonad axis and cause ovulation.
3) Environmental methods manipulate factors like temperature, water volume, pH or salinity to mimic natural cues and trigger final oocyte maturation and spawning. Precise cues vary between species.
This document discusses the natural food and feeding habits of fishes. It covers different types of plankton, benthos, and detritus that serve as food sources for fishes based on their ecological niche. Various feeding classifications are described, including feeding types, trophic niches, and quantitative analyses of gut content. Structural modifications in fishes related to their different feeding habits are also mentioned.
This document discusses the feeding habits of fish. It begins by defining feeding habit as the kind of food an animal habitually consumes during its life or at a particular stage. It then describes different modes of feeding such as herbivores, omnivores, carnivores, and limnivores. The document highlights that understanding the feeding habits of fish is important for polyculture systems. It also discusses the major types of feeding like grazing, predation, straining, sucking, and parasitism. Finally, it provides examples of different mouth structures in fish and how they relate to the fish's diet.
This document presents different culture methods for farming mussels. There are three main types of culture methods: bottom culture, intertidal and shallow water culture, and deep water culture. Intertidal and shallow water culture methods include rack culture, tray culture, wig-wam culture, and rope-web culture. Rack culture involves hanging mussel collectors on bamboo poles. Tray culture uses bamboo or metal trays suspended on poles. Deep water culture methods are raft culture, using rafts to hold suspended rope collectors, and long-line culture, which uses underwater lines anchored at the bottom.
The document provides information on the external and internal anatomy of finfish. It discusses the ten body systems of fish and the three main classes of fish - Agnatha, Chondrichthyes, and Osteichthyes. It describes the external anatomy including common body forms, body covering, scales, and fins. It details the internal anatomy covering organs like the brain, esophagus, stomach, and more. It also discusses the structure, types, and arrangements of scales and fins in more detail.
The document discusses the global ornamental fish trade and breeding of popular species. It provides details on the production of egg-laying fish like goldfish and angel fish which require different care depending on parental behaviors. Methods for breeding live-bearing fish such as guppies, platies, swordtails and mollies are also outlined, noting internal fertilization and live birth of young.
1) Artemia, or brine shrimp, are used as a live food source for fish and shellfish larvae. Their unique ability to form dormant cysts allows large quantities to be harvested and stored for on-demand hatching.
2) Upon incubation in seawater, the cysts release free-swimming nauplii that serve as a nutritious live food.
3) Artemia has a complex life cycle where it grows through 15 molts from nauplius to adult, and can reproduce rapidly through ovoviviparous or oviparous means.
The document covers several topics related to reproduction, early life stages, and growth in aquatic organisms. It discusses hormones that regulate reproduction, methods for inducing spawning in captive species, early life stage development from fertilization to juvenile growth, and concepts of growth measurement and patterns. Measurement of growth includes length, weight, and body composition assessments to monitor health and predict harvest times.
This document discusses the natural food and feeding habits of fishes. It covers different types of plankton, benthos, and detritus that serve as food sources for fishes based on their ecological niche. Various feeding classifications are described, including feeding types, trophic niches, and quantitative analyses of gut content. Structural modifications in fishes related to their different feeding habits are also mentioned.
This document discusses the feeding habits of fish. It begins by defining feeding habit as the kind of food an animal habitually consumes during its life or at a particular stage. It then describes different modes of feeding such as herbivores, omnivores, carnivores, and limnivores. The document highlights that understanding the feeding habits of fish is important for polyculture systems. It also discusses the major types of feeding like grazing, predation, straining, sucking, and parasitism. Finally, it provides examples of different mouth structures in fish and how they relate to the fish's diet.
This document presents different culture methods for farming mussels. There are three main types of culture methods: bottom culture, intertidal and shallow water culture, and deep water culture. Intertidal and shallow water culture methods include rack culture, tray culture, wig-wam culture, and rope-web culture. Rack culture involves hanging mussel collectors on bamboo poles. Tray culture uses bamboo or metal trays suspended on poles. Deep water culture methods are raft culture, using rafts to hold suspended rope collectors, and long-line culture, which uses underwater lines anchored at the bottom.
The document provides information on the external and internal anatomy of finfish. It discusses the ten body systems of fish and the three main classes of fish - Agnatha, Chondrichthyes, and Osteichthyes. It describes the external anatomy including common body forms, body covering, scales, and fins. It details the internal anatomy covering organs like the brain, esophagus, stomach, and more. It also discusses the structure, types, and arrangements of scales and fins in more detail.
The document discusses the global ornamental fish trade and breeding of popular species. It provides details on the production of egg-laying fish like goldfish and angel fish which require different care depending on parental behaviors. Methods for breeding live-bearing fish such as guppies, platies, swordtails and mollies are also outlined, noting internal fertilization and live birth of young.
1) Artemia, or brine shrimp, are used as a live food source for fish and shellfish larvae. Their unique ability to form dormant cysts allows large quantities to be harvested and stored for on-demand hatching.
2) Upon incubation in seawater, the cysts release free-swimming nauplii that serve as a nutritious live food.
3) Artemia has a complex life cycle where it grows through 15 molts from nauplius to adult, and can reproduce rapidly through ovoviviparous or oviparous means.
The document covers several topics related to reproduction, early life stages, and growth in aquatic organisms. It discusses hormones that regulate reproduction, methods for inducing spawning in captive species, early life stage development from fertilization to juvenile growth, and concepts of growth measurement and patterns. Measurement of growth includes length, weight, and body composition assessments to monitor health and predict harvest times.
Fertilized fish eggs are known as Fish seeds. In simple words, they are the baby fishes used for seeding new Ponds in fisheries. Fish seed transportation is a process by which transfer of fish seed from the hatchery or place of collection to the rearing ponds.
This document provides an overview of various fishing gears and methods. It begins with an outline of the course topics, which include the study and classification of fishing gears and crafts. It then describes different gear types such as beam trawling, demersal otter trawling, dredging, drift nets, fish attraction devices, gill/fixed nets, handlines, jigging, longlining, pelagic trawling, pole and line fishing, and pots. For each gear type, it explains how it is used to target particular species. The document provides a comprehensive reference for different fishing techniques around the world.
This document outlines various behaviors studied in behavioral ecology, including feeding behavior, predation, parasitism, mutualism, and communication. It discusses how feeding behavior is regulated by environmental and homeostatic factors. Predation behaviors in different fish species are described, as well as how predators and prey can control each other's populations. Competition between species and intraspecific competition are examined, including examples of resource partitioning and differential exploitation. The document also summarizes symbiotic relationships like mutualism, commensalism, and parasitism in fish, and covers behaviors like migration, schooling, camouflage, and sound/chemical communication.
The document provides an overview of catfish farming in the United States. It discusses that the channel catfish is the primary species farmed, with top producing states being Arkansas, Mississippi, Alabama and Louisiana. Catfish farming developed commercially in the 1960s in the southern US. Catfish are raised in ponds and fed prepared feeds containing protein, vitamins and minerals. Farming involves breeding stock, hatching eggs, and raising fry in ponds until harvesting at 1-1.5 pounds. Water quality, disease prevention and intermittent harvesting are important aspects of management and health.
This document discusses sex reversal in fish through hormone treatment. It explains that in early development, gonads can differentiate into either testes or ovaries, and hormones guide this process. Sex reversal has been achieved by turning males into females and vice versa. Temperature and hormone treatments before phenotypic sex development can cause total functional sex reversal. The document outlines different hormone treatment methods, examples of steroid hormones used, and considerations for successful and sustainable sex reversal programs.
TOPIC – INTRODUCTION OF EXOTIC FISH SPECIES.pptxSmriti Biswas
This document summarizes the introduction of exotic fish species in India. It discusses the history of exotic fish introductions dating back to 1863. Several exotic species have been introduced for aquaculture and mosquito control, with varying degrees of success and impacts. While exotic species can improve production and diversification, they also negatively impact native species through competition, predation, disease transmission, and genetic dilution. Proper evaluation and regulation of introductions is needed to balance these impacts and benefits.
I am uploading the Presentation on Genetically Improved Farmed Tilapia (GIFT). Tilapia is 3rd largest most prefered fish in world which is cultured in 75 countries. This presentation may be helpful to the students of Aquaculture.
Transport of hatchlings, fry, and fingerlings is common in aquaculture. Proper techniques involve understanding fish physiology and mortality causes during transport. Seed can be collected from wild or hatcheries. Major carps are collected from flooded rivers during monsoon season. Seed from estuaries and coastal waters include milkfish, mullets, pearlspot, and seabass. Bundhs are seasonal flooded areas that stimulate breeding. Induced spawning techniques breed species that don't spawn in captivity using hormones. Transport uses open or closed oxygenated systems. Factors causing mortality are oxygen depletion, waste accumulation, temperature fluctuations, and stress. Anaesthetics and antibiotics are used to reduce stress and prevent disease.
This document provides information about mussel farming techniques in India. It discusses the following key points:
1. China is the world's largest producer of cultured mussels. In India, mussel culture is popular along the Malabar coast, where the two main species farmed are Perna viridis and Perna indica.
2. Common mussel farming techniques used in India include raft culture, rack culture, and long-line culture. Raft culture is conducted in deep coastal waters using rafts up to 8x8 meters with seeded ropes suspended below.
3. Rack culture is used in shallow waters up to 3 meters deep, using wooden frames built on poles to suspend seeded ropes or bags
This document discusses polyculture of carp fish in Bangladesh. It describes that polyculture involves culturing multiple fish species together that have different feeding habits and ecological niches. Common carp species cultured together in Bangladesh include various types of indigenous carp like rohu, mrigal carp, and exotic carp like silver carp. Effective polyculture management requires selecting compatible species, maintaining suitable water quality parameters, providing adequate natural and supplemental food, monitoring fish health and growth, and preventing diseases. Polyculture aims to maximize fish production from a water body by fully utilizing available resources.
This document provides an overview of reproductive biology in fishes. It discusses the different types of sexuality observed in fishes, including unisexuality, bisexuality, hermaphroditism, and parthenogenesis. It describes the reproductive cycles and hormones that regulate reproduction for both male and female fish. Key aspects covered include the gonads, sexual dimorphism, seasonal breeding patterns, and hormonal control of the reproductive system through the CNS-pituitary-gonad axis.
1. Rotifers are commonly used live feed for marine fish larvae. They are small, tolerate a wide range of conditions, and reproduce rapidly.
2. Mass culture of rotifers involves three units - one for culturing algae food, one for stock culture, and one for large-scale production. Proper temperature, pH, salinity, and aeration are needed.
3. Rotifers are enriched by feeding them algae rich in omega-3 fatty acids to increase their nutritional value for fish larvae. Enriched rotifers are stored at low temperatures to preserve fatty acid levels.
This document discusses different types of fish migration. It describes potamodromous migration within freshwater systems, oceanodromous migration within marine systems, and diadromous migration between freshwater and marine systems. Diadromous migration includes catadromous migration patterns like eels that live in freshwater but spawn in the ocean, and anadromous patterns like salmon that live in the ocean but spawn in freshwater rivers and streams. The document provides details on the life cycles and migration routes of eels and salmon.
This document discusses the feeding habits and nutritional requirements of fish at different life stages. It begins by explaining that fish require energy, amino acids, fatty acids, vitamins, and minerals to sustain life and promote growth. It then discusses the feeding behaviors and nutritional needs of fish larvae, including their underdeveloped digestive systems and reliance on plankton and zooplankton. The document also categorizes different types of food sources for fish and classifies fish based on their dependence on food types and positions in the water column. Specific examples are provided of the feeding behaviors of fish larvae, juveniles, and adults.
Bundhs are tanks or impoundments that simulate riverine conditions for carp breeding during monsoon months. Dry bundhs are seasonal while wet bundhs are perennial. Dry bundhs, popular in West Bengal and Madhya Pradesh, consist of storage ponds, hatcheries, and sluice gates for draining water to allow multiple spawnings per season. Wet bundhs in West Bengal are larger ponds that fill with monsoon rainfall, providing a single annual spawning opportunity. Both bundh types provide controlled environments to induce carp breeding through water level manipulation.
This document discusses the culture methods for the rotifer Brachionus plicatilis, an important live feed for larval marine animals. It describes how to maintain stock cultures in 1-2L flasks using Isochrysis galbana algae at 24-25C under a 12:12 light cycle. Main culture methods discussed are using various tank sizes from 50L to 1800L, sterilizing tanks with bleach, and maintaining temperature at 24-26C with lighting. Feeding protocols are provided using yeast, fish oil, and algae to culture rotifers from low to high densities. Rotifers are harvested daily and fed to larval fish starting at 3 days post hatch at 3
The document summarizes information about the cultivation of edible oysters. It discusses the different species of edible oysters found in India, methods of seed production including hatchery techniques, farming methods such as extensive and intensive culture, and processing after harvest including depuration, shucking, and packaging. The key stages of oyster hatchery operation are also outlined including broodstock selection and spawning, larval rearing, and spat collection and nursery culture. Site selection criteria and common pests affecting oyster farms are also mentioned.
This document discusses different aspects of fishery management and regulation. It begins by outlining the three main activities of fishery management: regulation of fishing, environmental management, and artificial stock enhancement. It then discusses the origins of public policy around fishing and ownership of fish resources. The document goes on to outline current objectives of fishing regulation such as conservation and allocation of fishing rights. It also describes different methods that are used to regulate fishing.
This document provides information on sea cucumbers (holothurians), including their biology, life cycle, reproduction, and aquaculture. It discusses that holothurians are economically important as food and that their skin and muscle layers are edible. It also describes their internal anatomy, feeding behavior, spawning season from March to April when eggs and sperm are released, and larval development. The document outlines aquaculture techniques for sea cucumbers such as pond culture and discusses broodstock maintenance and artificial breeding.
A SEMINAR ON INDUCING AGENTS OF HYPOPHYSATIONKartik Mondal
The precise combination of environmental factors required for maturation, ovulation and spawning.
However, quite often, under farm conditions, the requisite environmental factors are either not available or do not persist for sufficient length of time for spontaneous maturation to occur.
The pioneering discovery of B.A. Houssay (1931) and Von Ihering (1935, 1937, Argentina) that fishes can be induced to spawn by injecting pituitary homogenates has somewhat mitigated the problem.
The principal advantage of this technique, referred to in aquaculture parlance as “Hypophysation.”
Control of gonad growth, maturation and spawning in teleost fish aWiwinUMRAH
This document summarizes the control of gonad growth, maturation, and spawning in teleost fish. It discusses that gonad development is controlled by the hypothalamus-pituitary axis, with two gonadotropins (GtH I and II) regulating growth and final maturation. Environmental cues can trigger the neuroendocrine system to stimulate gonad development, while direct interventions can also influence the neuroendocrine cascade. The review covers recent advances in understanding the roles of the pituitary hormones like GtH I and II as well as growth hormone, and the hypothalamic control mechanisms involving GnRH and other peptides and amines that regulate GtH secretion.
Fertilized fish eggs are known as Fish seeds. In simple words, they are the baby fishes used for seeding new Ponds in fisheries. Fish seed transportation is a process by which transfer of fish seed from the hatchery or place of collection to the rearing ponds.
This document provides an overview of various fishing gears and methods. It begins with an outline of the course topics, which include the study and classification of fishing gears and crafts. It then describes different gear types such as beam trawling, demersal otter trawling, dredging, drift nets, fish attraction devices, gill/fixed nets, handlines, jigging, longlining, pelagic trawling, pole and line fishing, and pots. For each gear type, it explains how it is used to target particular species. The document provides a comprehensive reference for different fishing techniques around the world.
This document outlines various behaviors studied in behavioral ecology, including feeding behavior, predation, parasitism, mutualism, and communication. It discusses how feeding behavior is regulated by environmental and homeostatic factors. Predation behaviors in different fish species are described, as well as how predators and prey can control each other's populations. Competition between species and intraspecific competition are examined, including examples of resource partitioning and differential exploitation. The document also summarizes symbiotic relationships like mutualism, commensalism, and parasitism in fish, and covers behaviors like migration, schooling, camouflage, and sound/chemical communication.
The document provides an overview of catfish farming in the United States. It discusses that the channel catfish is the primary species farmed, with top producing states being Arkansas, Mississippi, Alabama and Louisiana. Catfish farming developed commercially in the 1960s in the southern US. Catfish are raised in ponds and fed prepared feeds containing protein, vitamins and minerals. Farming involves breeding stock, hatching eggs, and raising fry in ponds until harvesting at 1-1.5 pounds. Water quality, disease prevention and intermittent harvesting are important aspects of management and health.
This document discusses sex reversal in fish through hormone treatment. It explains that in early development, gonads can differentiate into either testes or ovaries, and hormones guide this process. Sex reversal has been achieved by turning males into females and vice versa. Temperature and hormone treatments before phenotypic sex development can cause total functional sex reversal. The document outlines different hormone treatment methods, examples of steroid hormones used, and considerations for successful and sustainable sex reversal programs.
TOPIC – INTRODUCTION OF EXOTIC FISH SPECIES.pptxSmriti Biswas
This document summarizes the introduction of exotic fish species in India. It discusses the history of exotic fish introductions dating back to 1863. Several exotic species have been introduced for aquaculture and mosquito control, with varying degrees of success and impacts. While exotic species can improve production and diversification, they also negatively impact native species through competition, predation, disease transmission, and genetic dilution. Proper evaluation and regulation of introductions is needed to balance these impacts and benefits.
I am uploading the Presentation on Genetically Improved Farmed Tilapia (GIFT). Tilapia is 3rd largest most prefered fish in world which is cultured in 75 countries. This presentation may be helpful to the students of Aquaculture.
Transport of hatchlings, fry, and fingerlings is common in aquaculture. Proper techniques involve understanding fish physiology and mortality causes during transport. Seed can be collected from wild or hatcheries. Major carps are collected from flooded rivers during monsoon season. Seed from estuaries and coastal waters include milkfish, mullets, pearlspot, and seabass. Bundhs are seasonal flooded areas that stimulate breeding. Induced spawning techniques breed species that don't spawn in captivity using hormones. Transport uses open or closed oxygenated systems. Factors causing mortality are oxygen depletion, waste accumulation, temperature fluctuations, and stress. Anaesthetics and antibiotics are used to reduce stress and prevent disease.
This document provides information about mussel farming techniques in India. It discusses the following key points:
1. China is the world's largest producer of cultured mussels. In India, mussel culture is popular along the Malabar coast, where the two main species farmed are Perna viridis and Perna indica.
2. Common mussel farming techniques used in India include raft culture, rack culture, and long-line culture. Raft culture is conducted in deep coastal waters using rafts up to 8x8 meters with seeded ropes suspended below.
3. Rack culture is used in shallow waters up to 3 meters deep, using wooden frames built on poles to suspend seeded ropes or bags
This document discusses polyculture of carp fish in Bangladesh. It describes that polyculture involves culturing multiple fish species together that have different feeding habits and ecological niches. Common carp species cultured together in Bangladesh include various types of indigenous carp like rohu, mrigal carp, and exotic carp like silver carp. Effective polyculture management requires selecting compatible species, maintaining suitable water quality parameters, providing adequate natural and supplemental food, monitoring fish health and growth, and preventing diseases. Polyculture aims to maximize fish production from a water body by fully utilizing available resources.
This document provides an overview of reproductive biology in fishes. It discusses the different types of sexuality observed in fishes, including unisexuality, bisexuality, hermaphroditism, and parthenogenesis. It describes the reproductive cycles and hormones that regulate reproduction for both male and female fish. Key aspects covered include the gonads, sexual dimorphism, seasonal breeding patterns, and hormonal control of the reproductive system through the CNS-pituitary-gonad axis.
1. Rotifers are commonly used live feed for marine fish larvae. They are small, tolerate a wide range of conditions, and reproduce rapidly.
2. Mass culture of rotifers involves three units - one for culturing algae food, one for stock culture, and one for large-scale production. Proper temperature, pH, salinity, and aeration are needed.
3. Rotifers are enriched by feeding them algae rich in omega-3 fatty acids to increase their nutritional value for fish larvae. Enriched rotifers are stored at low temperatures to preserve fatty acid levels.
This document discusses different types of fish migration. It describes potamodromous migration within freshwater systems, oceanodromous migration within marine systems, and diadromous migration between freshwater and marine systems. Diadromous migration includes catadromous migration patterns like eels that live in freshwater but spawn in the ocean, and anadromous patterns like salmon that live in the ocean but spawn in freshwater rivers and streams. The document provides details on the life cycles and migration routes of eels and salmon.
This document discusses the feeding habits and nutritional requirements of fish at different life stages. It begins by explaining that fish require energy, amino acids, fatty acids, vitamins, and minerals to sustain life and promote growth. It then discusses the feeding behaviors and nutritional needs of fish larvae, including their underdeveloped digestive systems and reliance on plankton and zooplankton. The document also categorizes different types of food sources for fish and classifies fish based on their dependence on food types and positions in the water column. Specific examples are provided of the feeding behaviors of fish larvae, juveniles, and adults.
Bundhs are tanks or impoundments that simulate riverine conditions for carp breeding during monsoon months. Dry bundhs are seasonal while wet bundhs are perennial. Dry bundhs, popular in West Bengal and Madhya Pradesh, consist of storage ponds, hatcheries, and sluice gates for draining water to allow multiple spawnings per season. Wet bundhs in West Bengal are larger ponds that fill with monsoon rainfall, providing a single annual spawning opportunity. Both bundh types provide controlled environments to induce carp breeding through water level manipulation.
This document discusses the culture methods for the rotifer Brachionus plicatilis, an important live feed for larval marine animals. It describes how to maintain stock cultures in 1-2L flasks using Isochrysis galbana algae at 24-25C under a 12:12 light cycle. Main culture methods discussed are using various tank sizes from 50L to 1800L, sterilizing tanks with bleach, and maintaining temperature at 24-26C with lighting. Feeding protocols are provided using yeast, fish oil, and algae to culture rotifers from low to high densities. Rotifers are harvested daily and fed to larval fish starting at 3 days post hatch at 3
The document summarizes information about the cultivation of edible oysters. It discusses the different species of edible oysters found in India, methods of seed production including hatchery techniques, farming methods such as extensive and intensive culture, and processing after harvest including depuration, shucking, and packaging. The key stages of oyster hatchery operation are also outlined including broodstock selection and spawning, larval rearing, and spat collection and nursery culture. Site selection criteria and common pests affecting oyster farms are also mentioned.
This document discusses different aspects of fishery management and regulation. It begins by outlining the three main activities of fishery management: regulation of fishing, environmental management, and artificial stock enhancement. It then discusses the origins of public policy around fishing and ownership of fish resources. The document goes on to outline current objectives of fishing regulation such as conservation and allocation of fishing rights. It also describes different methods that are used to regulate fishing.
This document provides information on sea cucumbers (holothurians), including their biology, life cycle, reproduction, and aquaculture. It discusses that holothurians are economically important as food and that their skin and muscle layers are edible. It also describes their internal anatomy, feeding behavior, spawning season from March to April when eggs and sperm are released, and larval development. The document outlines aquaculture techniques for sea cucumbers such as pond culture and discusses broodstock maintenance and artificial breeding.
A SEMINAR ON INDUCING AGENTS OF HYPOPHYSATIONKartik Mondal
The precise combination of environmental factors required for maturation, ovulation and spawning.
However, quite often, under farm conditions, the requisite environmental factors are either not available or do not persist for sufficient length of time for spontaneous maturation to occur.
The pioneering discovery of B.A. Houssay (1931) and Von Ihering (1935, 1937, Argentina) that fishes can be induced to spawn by injecting pituitary homogenates has somewhat mitigated the problem.
The principal advantage of this technique, referred to in aquaculture parlance as “Hypophysation.”
Control of gonad growth, maturation and spawning in teleost fish aWiwinUMRAH
This document summarizes the control of gonad growth, maturation, and spawning in teleost fish. It discusses that gonad development is controlled by the hypothalamus-pituitary axis, with two gonadotropins (GtH I and II) regulating growth and final maturation. Environmental cues can trigger the neuroendocrine system to stimulate gonad development, while direct interventions can also influence the neuroendocrine cascade. The review covers recent advances in understanding the roles of the pituitary hormones like GtH I and II as well as growth hormone, and the hypothalamic control mechanisms involving GnRH and other peptides and amines that regulate GtH secretion.
The document covers several topics related to reproduction, early life stages, and growth in aquatic organisms. It discusses hormones that regulate reproduction, methods for inducing spawning in captive fish, early life stage development including embryogenesis and larval stages, and concepts of growth including measurements and patterns of growth. Key growth measurements mentioned are length, weight, dry weight, and condition factor.
The document covers several topics related to reproduction, early life stages, and growth in aquatic organisms. It discusses hormones that regulate reproduction, methods for inducing spawning in captive species, early life stage development including embryogenesis and larval stages, and concepts of growth including measurements and patterns of growth. Key growth measurements mentioned are length, weight, dry weight, and condition factor. The document provides an overview of these essential topics but some specifics like formulas and tables are noted as not required reading.
The document covers several topics related to reproduction, early life stages, and growth in aquatic organisms. It discusses hormones that regulate reproduction, methods for inducing spawning in captive fish, early life stage development including embryogenesis and larval stages, and concepts of growth including measurements and patterns of growth. Captive spawning techniques aim to control timing and number of seeds available and are preferred over collecting from nature. Hormones regulate reproduction and gamete release in the brain, pituitary gland, and gonads.
BASIC STEPS IN IN VITRO FERTILIZATION (IVF)Wasiu Adeseji
The document summarizes the basic steps in in vitro fertilization (IVF). It begins with pituitary suppression and ovarian hyperstimulation to develop multiple follicles. Mature eggs are then retrieved from the ovaries through transvaginal ultrasound-guided needle aspiration. Sperm is collected and prepared for fertilization through sperm washing. The eggs and sperm are then fertilized through either insemination or intracytoplasmic sperm injection. The fertilized eggs are cultured for 2-6 days until embryo transfer into the uterus. Success rates vary based on factors like maternal age but average live birth rates in the US range from about 30-40% per cycle for women under 35.
Anestrus occur in different animals. Anestrus may be due to physiological or pathological factors. Veterinary drugs are now available to treat or reverse anestrus in animals.
This study investigated the role of glycerol biosynthesis in lifespan extension from hyperosmotic conditions in C. elegans. The authors found that both 10x peptone and 5% sorbitol conditions increased wild type C. elegans lifespan by around 35%, but this lifespan extension was absent in gpdh-1;gpdh-2 mutant worms, which are unable to accumulate glycerol. Future experiments will determine if overexpressing glycerol biosynthesis is sufficient to extend lifespan without osmotic stress. This supports the role of glycerol accumulation, mediated by glycerol 3-phosphate dehydrogenase, in the longevity response to hyperosmotic stress in C. elegans.
Probable False Positive Finding of Rodent Prenatal Toxicity for a High Molecu...Joseph Holson
Introductory presentation ("Overview of Issues Concerning False Positive Findings in Reproductive Toxicology and Introduction of a Case Study of an Oxygen Therapeutic") in Symposium I ("A Detective Story: Is the Prenatal Toxicity of a Therapeutic in Rats Relevant to Human Risk?", Joseph F. Holson and L. B. Pearce, co-chairpersons) at the Forty-Third Annual Meeting of the Teratology Society, Philadelphia, PA, June 26, 2003.
This summary provides the key points from the document in 3 sentences:
The document discusses a study that conditionally deleted the GATA4 and GATA6 transcription factor genes in mouse adrenocortical cells. The researchers found that mice with double deletion of these genes lacked identifiable adrenal glands, adrenocortical cells, and steroidogenic gene expression. Additionally, deletion of GATA6 alone significantly reduced adrenal size and function in adult mice, revealing that GATA factors are required for proper adrenal development and function.
This study examined the effects of human chorionic gonadotropin (hCG) on oocyte maturation in the freshwater fish Barilius vagra. In vitro experiments showed that hCG exposure resulted in a time-dependent maturation of oocytes, as indicated by migration and breakdown of the germinal vesicle. HCG also stimulated the production of estradiol, progesterone, and other steroids, and electron microscopy revealed morphological changes in granulosa
this talks about the nutritional factors that are associated with the spawning, maturation growth and reproduction of fishes. and the recently advanced feeds
Special Issue:What hormones are typically used for fish sex reversal.pdfAASraw
Male fish are generally heavier and grow faster than female fish. Therefore, in order to ensure the supply of fish meat to the greatest extent, people use sex control technology to increase the yield and variety of fish under the premise of ensuring that exogenous hormones are harmless to the human body.
2013 List_The role of GH in adipose tissue-LiGHRKO miceEdward List
1) The study generated mice with the GH receptor gene specifically disrupted in adipose tissue (FaGHRKO mice) to clarify the role of GH in adipose tissue.
2) FaGHRKO mice were obese with increased total body fat and enlarged adipocytes, similar to global GHR knockout mice. However, FaGHRKO mice did not show improvements in glucose homeostasis or increased levels of resistin and adiponectin like global knockouts.
3) Specific removal of the GH receptor in adipose tissue was sufficient to increase adiposity and decrease circulating adipsin, but did not alter glucose metabolism or increase resistin or adiponectin levels. This suggests GH does not directly regulate these factors
HISTOCHEMICAL STUDIES OF ENZYMES INVOVED IN HORMONAL REGULATION IN GARDEN LIZ...paperpublications3
Abstract: Studies in situ changes in various enzyme activities viz. ∆5-3β-HSDH, Peroxidase, Acid and Alkaline phosphatases, Cytochrome oxidase &Lipids in the adrenal gland and ovary at different stages of reproductive cycle in Garden Lizard (Calotes versicolor). Peroxidase appears to be involved in the biosynthetic machinery controlling corticosteroidogenesis. Peroxidase and Cytochrome oxidase would also seem to transform adrenocortical cells and hypertrophied theca interna into highly oxidative compartments of the adrenal and ovary which attributes to the oxidation of pregnenolone to progesterone and corticosteroids towards maturation and ovulation of the oocyte from the ovary.
Biochemical Changes in Ascorbate and Peroxidase Activity in the Adrenal Gland...paperpublications3
This document discusses biochemical changes in ascorbate and peroxidase activity in the adrenal gland during different stages of the reproductive cycle in rats. It finds that peroxidase activity increases and ascorbate levels decrease during diestrous and proestrous, when ACTH levels are high. This suggests peroxidase may be involved in the rapid conversion of pregnenolone to progesterone in the adrenal gland. The adrenal gland produces sex hormones like progesterone until the ovaries mature, and progesterone levels have been found to fluctuate across the estrous cycle. High peroxidase activity in the adrenal cortex may be correlated with increased progesterone synthesis and secretion.
Ovarian hyperstimulation syndrome (OHSS) is an iatrogenic condition caused by fertility treatments. It can range from mild to life-threatening. Steps to prevent OHSS include identifying at-risk patients, using low gonadotropin doses, coasting by withholding gonadotropins to lower estrogen levels safely, using GnRH antagonists, and administering metformin. If OHSS occurs, management focuses on investigations, fluid monitoring, and paracentesis if needed.
HISTOCHEMICAL STUDIES OF ENZYMES INVOVED IN HORMONAL REGULATION IN GARDEN LI...paperpublications3
Abstract: Studies in situ changes in various enzyme activities viz. ∆5-3β-HSDH, Peroxidase, Acid and Alkaline phosphatases, Cytochrome oxidase &Lipids in the adrenal gland and ovary at different stages of reproductive cycle in Garden Lizard (Calotes versicolor). Peroxidase appears to be involved in the biosynthetic machinery controlling corticosteroidogenesis. Peroxidase and Cytochrome oxidase would also seem to transform adrenocortical cells and hypertrophied theca interna into highly oxidative compartments of the adrenal and ovary which attributes to the oxidation of pregnenolone to progesterone and corticosteroids towards maturation and ovulation of the oocyte from the ovary.
Keywords: Biosynthetic Machinery, Enzymes, Adrenal-Ovary Interrelation & Pregnenolone to Progesterone, Corticosteroidogenesis.
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Induced spawning in fin fishes group1
1. INDUCED SPAWNING
IN FIN FISHES
Aparri, Benjie P.
Bete, Gemma C.
Fuentes, Jolina
Suganob, Queenilyn
Porlares, Mary Grace
Mercado, Orlando
2. • Species that didn’t reproduce in captivity
• Obtain fish supply outside of the normal spawning
season; important for intensive culture
• Develop superior strains through selective breeding
& hybridization methods
• Maximize survival;
1% natural spawning; 65% induced spawning
Induced spawning
2
3. Physiological Processes
In the female fish, induced spawning normally is
carried out at the end of vitellogenesis (i.e.
tertiary yolk granule or globule stage) and
involves the induction of germinal vesicle
migration to the periphery (sometimes induced
spawning may start from this stage), germinal
vesicle breakdown (GVBD) or final oocyte
maturation, ovulation and oviposition; the last
step may be replaced by stripping.
4. In the male process involved are
spermiation (release of spermatozoa from
the Sertoli cells into the tubules or lobules)
(Baynes and Scott, 1985), thinning of the
seminal fluid or Plasma (seminal hydration,
which should be considereo separately from
spermlation) (Bayries and Scott 1985), and
ejaculation release to the outside) or
stripping.
5. There are two approaches to induction of
spawning in fishes: (I)hormonal and
(II)environmental. The two approaches may be
combined to achieve the best effect. After
treatment, the fish in each approach may be
stripped for artificial fertilization or left for
natural spawning. Whether the ovulated eggs
are fertilized artificially or naturally, the fertilized
eggs are incubated, and the hatched larvae to fry
stage in the hatchery.
6. Hormonal Approach
This is based on an understanding of the
neuroendocrine control of oocyte maturation,
ovulation and spawning behaviour(see reviews
by Goetz, 1983; Liley and Stacey (1983) in the
female, and oF spermiation and seminal
hydration in In general, our present
understanding of the subject in the female may
be summarized as follows:
7. 1. Stimulation of the release of
gonadotropin-releasing Hormone GnRH
and/or inhibition of the release of
gonadotropin release-inhibiting factor
(GnRIF) causes the pituitary to secrete
gonadotropin (GtH) into the bloodstream
(Peter, 1983).
8. 2. When a certain level of GtH is
reached, a germinal vesicle migrates to
the periphery and the theca and
granulosa cells of the follicle are
stimulated to secrete a maturation
inducing steroid.
9. 3. The MIS induces GVBD (resumption of meiosis) and
also probably other associated events, e.g. Hydration
and coalescence of yolk granules seen in some
species. Evidence points to 17 ct -hydroxy-20f
dihydroprogesterone (17 t20r-P) as the MIS although
corticosteroids have also been implicated. It is
suggested that corticosteroids play only a supportive
role: they may displace 17(t-20 -P bound to plasma
protien inand/or increase oocyte sensitivity to 174 -
20B – P (Jalabert, 1976).
10. Fish Pituitary Extract
The use of pituitary induce fish extracts to
spawning (hypophysation) has been practiced
since 1931 when Houssay first introduced the
technique. It still is widely used. The pituitary
glands used usually are obtained from sexually
maturing or mature donor fish that may be of
the same or different, species. They can be used
freh or stored for subsequent use.
11. Hypophysation is a simple and practical
technique but suffers from the disadvantage,
that the gonadol.opic potency of the pituitary
glands used often is unknown and is difficult to
standardize. One possible solution is to use
commercially available acetone-dried or
lyophilized pituitary powder that has been
assayed for gonadotropin content (e.g. salmon
pituitary powder from Syndel Laboratories Ltd,.
Vancouver, Canada).
12. It is interesting that a low dose of 1 mg pituitary carp
per kg body weight induced oocyte maturation
without ovulation in the golden perch, macquaria
ambigua. Whereas a 15 mg/kg caused a decline in
hatchability compared to 10 mg/kg, which appeared to
be the optimal dosagein this species (Rowland, 1983);
5 mg/kg also inducethe fertilization rate was more
variable than with 10 mg/kg. Another point of
interest is that in two species of catfish Clarias
macrocephalus and Rhada sap, the response time to
ovulation was 13 h at around 27°C.
13. Human Chorionic Gonadotropin (HCG)
HCG has been used successfully to induce
ovulation/spawning in a number of species (see reviews
by Lam, 1982; Donaldson and Hunter, 1983). The
dosage required may vary in different species
depending on how closely related the
endogenous gonadotropin is to HCG (Lam, 1982).
However, the dose-response relationship has not
be3n studied in most cases.
14. HCG also has recently been used to
induce spawning in milkfish, CbAs
han review Liao Chen, ang (see by and
1984), curimbata, PchQCbiQ-dus 5La
(Fenerich-Verani et al., 1984), white
seabream, Myli bge£a (Mok, 1985),
and rabbitfish, Sigdnus gu-tatus
(Juario et al., 1985).
15. HOG and Hypophysation
A combination of HOG and hypophysation
has been shown to be effective in inducing
ovulation or spawning in several species . However, a
careful evaluation of this combination treatment
versus HCG or hypophysation alone has not been
cone often. Recently, Rowland (1983) has shown
that the combination treatment was not any
more effective than ither HOG or hypophysation
alone in M. ambigua.
16. Furthermore, milkfish, which were thought to require
HOG plus hypophysation can be spawned by HCG
alone. However, this may be related to the condition
or age of the fish: wild fish of unknown age were used
in the former studies, while captive broodstock or 8-
10 year old fish were used in the latter. In contrast, a
single combined injection of homoplastic pituitary
extract with HCG was more effective in inducing production
of normal fertilizable ovulated eggs than single or
multiple injections of pituitary extract alone in
Prochilidus platensia (Espinach Ros et al., 1984b).
17. Partially Purified or Purified Fish Gonadotropin
Preparations
Several partially purified or purified fish gonadotropin
preparations are now available from research laboratories
(see review by Donaldson and Hunter, 1983). Some
attempts have been made to use some of these
preparations to induce ovulation in fish (see reviews
by Lam, 1982; Donaldson and Hunter, 1983). Though
successful, they are at present not cost effective compared
to crude pituitary extract or HCG.
18. Luteinizing Hormone-Releasing Hormone (LHRH)
and its Analogues
LHRH is effective in inducing gonadotropin
release and ovulation in fish but its superactive
analogues (LHRH-A) are more effective. There is
increasing interest in the use of LHRH-A as an
ovulating agent in cultured fish species: Japanese
eel, European sea bass, salmonids and white
sturgeon.
19. Antiestrogens
Antiestrogens (clomiphene citrate, tamoxifen and cyclofenil) have been
shown to be effective in inducing ovulation in several species of
fish. They function by stimulating GtH secretion, presumably
through abatement of the negative feecback effects of endogenous
estrogens. As such, they probably would work best towards or at the end of
vitellogenesis when blood estrogen levels are high. As blood estrogen
levels subsequently drop rapidly during the subperipheral and
peripheral germinal vesicle stages and the germinal vesicle breakdown
stage, antiestrogens probably would not work as well if injected
into fish with oocytes at these stages. Another point to note is that
excessive doses of the antiestrogens may be estrogenic and inhibit
gonadotropin secretion instead.
20. Standardization
An induced spawning technique should as far as
possible be standardized against variables such as age of
spawner, initial gonadal stage, hormone dosage, time
interval between injections, time to stripping or spawning
from the last injection, time of injection during the day,
time of year (season), and environmental conditions. These have
been dicussed. Recent studies again have emphasized
the importance of considering some of these variables.
21. Age
It may be more difficult to induce spawning
in firsttime spawners than in experienced
spawners. In the rainbow trout, first-time
spawners often produce eggs of a wider range of
quality than older fish, and also are poorer sperm
producers than older fish.
22. Initial Gonadal Stage
In the rabbitfish (.S. Qu]atu.), fish with oocytes less
than 0.47 mm in diameter spawned only 37 after
HCG injections, and the smaller the initial egg
diameter, the more HCG (total dose) w:s required
(Juario et al., 1985). On the other hand, fish with oocytes larger
than 0.47 mm in diameter (characterized by
germinal vesicle migration) spawned without HCG
injection.
23. Time for Stripping or Spawning
Recent studies have provided more evidence that egg viability
declines rapidly because of overripening when stripping is delayed
beyond a certain species-and temperature-dependent period of
time after ovulation. There also is increasing evidence that between
the time when ovulation first occurs and the time when
overripening sets in, there is an optimal time for stripping that
gives the best fertilizability, hatchability and larval survival. In natural
spawning, there usally is a time lapse between ovulation and 38
oviposition; three to six hours in Japanese medaka. During this
period, the ovulated eggs may undergo further hydration and
other maturational changes.
24. Environmental Condition
Temperature certainly is an important factor to
consider; it affects the injection interval, response latency,
time to overripening, and ovarian responsiveness.
Salinity appeared to affect the ovulatory response of milkfish to
hormones factors also may be important. Recentlythere are
some undetermined environmental factors (not
vegetation) present in a pond situation that may
potentiate the ovulatory response of carp to LHRH-A.
25. Environmental Approach
This is based on the premise that for each species of fish, there may be
a specific, or a set of specific, environmental and/or social cues which
trigger final oocyte maturation and ovulation leading to spawning
behavior and spawning. In most species, particularly the tropical
species, the specific spawning cues have not been identified; only
suggestions have been made based on general observations without
any experimental evdence. Despite this paucity of specific information, the
environmental approach spawningto induction has been practiced
successfully in several species. Examples may be grouped in accordance to the degree
of specific environmental and/or social control exerted.
29. 1) Brood fish selection from nature or fish ponds
2) Brood fish rearing
3) Induce final maturation & ovulation with
hormone treatment
4) Treatment of the male & milt collection
5) Stripping of the female & egg collection
6) Artificial fertilization
7) Incubation & hatching of eggs
8) Larvae & fry rearing
Steps in artificial propagation
29
30. • External
- Shape of body (abdomen)
- Colour (Male => colourful)
- structure (Male => tubercles on operculum surface)
- Eggs/ milt
Sex Identification
30
32. INJECTION THE FISH
• Intraperitoneal – within the body cavity, behind either
pelvic or pectoral fin
• 2 dosage level
• A prepatory dose – brink of spawning
• A final dose – induces ovulation
• A time gap generally 12 to 24 hour between the
dose
33. • Some fish – difficult to strip
• Due to the anatomical structure – seminal
vesicles
• Need to sacrifice the fish to collect the milt
• Avoid contact with water or the spermatozoa lose
its ability to fertilize mature fish eggs.
• Milt can be stored in a refrigerator for 1-2 days
Male spawner
33